Covering arrangement for swimming pools

ABSTRACT

A covering arrangement for swimming pools or similar open areas in which a flexible cover has one end attached to a drum, and which may be wound onto the drum or rolled off from the drum. A reversible motor operates the drum for unwinding the cover when the motor operates in one direction of rotation. In the reverse direction of the motor, the cover is rolled off from the drum. A carriage serves to carry the drum which is provided with transport mechanisms on each side. A coupling arrangement connects the motor to the transport mechanisms when the motor rotates the drum for the purpose of unwinding the cover from the drum. When, on the other hand, the cover is to be wound onto the drum, the motor is connected by the coupling arrangement to the drum.

United States Patent 1 Vorbach et al.

[ May 27, 1975 COVERING ARRANGEMENT FOR SWIMMING POOLS [75] Inventors:Jiirg L. Vorbach, Riedlingen; Peter Tess, Ravensburg, both of Germany 22Filed: Apr. 25, 1974 21 Appl. No.: 463,569

[30] Foreign Application Priority Data 3,074,079 1/1963 Isaacson....

3,277,498 10/1966 Kleinbard et al. 4/l72.l4 3,418,667 l/l968 Powlan4/172.l4 3,747,132 7/1973 Foster 4/172.l4

Primary Examiner-Robert 1. Smith Attorney, Agent, or Firm-Max FogieiABSTRACT A covering arrangement for swimming pools or similar open areasin which a flexible cover has one end attached to a drum, and which maybe wound onto the drum or rolled off from the drum. A reversible motoroperates the drum for unwinding the cover when the motor operates in onedirection of rotation. In the reverse direction of the motor, the coveris rolled off from the drum. A carriage serves to carry the drum whichis provided with transport mechanisms on each side. A couplingarrangement connects the motor to the transport mechanisms when themotor rotates the drum for the purpose of unwinding the cover from thedrum. When, on the other hand, the cover is to be wound onto the drum,the motor is connected by the coupling arrangement to the drum.

21 Claims, 8 Drawing Figures COVERING ARRANGEMENT FOR SWIMMING POOLSBACKGROUND OF THE INVENTION The invention concerns a coveringarrangement for free areas, particularly swimming basins and pools, witha flexible cover attached at one end to a drum, and capable of beingrolled up on and off the drum which is operated by a motor.

Covering installations of this type are applicable to the covering ofmany different types of free areas, for example: green houses, roovers,tennis courts, atria, flower beds, etc. The installations areparticularly important for covering swimming pools or basins. Here thecover can rest on the water surface, and can be floatable, or it can beled along the edges of the basin. The cover can be formed from layers,or it can be rigid in the transverse direction and thereby be able tosupport at least children.

The main purposes of such covers in protection against pollution,temperature and humidity differences, particularly loss of heat. Thus,good heatinsulating materials are sometimes used.

Generally, the drum is in a fixed location at one end of the area to becovered, while the cover, which can be formed by rigid elements toconstitute a roll-blind type of structure, is pulled out by hand, andpulled in by a spring. Motor drives are also known for this purpose.

In an installation for covering tennis courts or similar areas, the drumhas been provided with a hand crank and installed on a cart that canalso be moved by hand. But here, the operation is particularlycumbersome and laborious.

Furthermore, there are covers made of zig-zag configurations of foldableplates, pulled out by a carriage driven by an electric motor. The coversare pulled out of either a fixed housing or a housing on the carriage.But such installations are expensive and subject to frequent failure.

Accordingly, it is an object of the present invention to provide acovering arrangement for any desired free areas, particularly swimmingbasins or pools, which is as simple and inexpensive as possible, iseasily operated without the use of manpower, and can be applied toinstallations already in existence.

SUMMARY OF THE INVENTION The objects of the present invention areachieved by providing a covering installation with a flexible coverwhich is attached at one end to a drum, and is capable of being rolledonto and off the drum which is operated by a motor. The drum isinstalled on a carriage that is transportable in a conventional mannerby a reversible transport motor and two lateral transport mechanisms.The transport motor can be coupled in its one direction of rotation tothe transport mechanisms for pulling out or unwinding the cover. Thetransport motor can be coupled in its other direction to the drum forrolling up the cover.

Here the cover itself is not in motion relative to the area to becovered, the cover is simply unrolled over the area, anad is taken upwhen being rolled up again. While rolling up the cover, the carriagepulls itself along the cover until it reaches the initial position.Thus, a lateral orientation is achieved that makes additional elements,such as rails and guide rollers, superfluous. The only control prevailsover the reversal of the direction of rotation of the transport motorand this can be carried out either directly at the carriage or at anyother point that can be electrically connected. This, then, permitsbetter supervision of the covering and rolling up processes. Thetechnical equipment and the weight of the carriage are so small, thatvery little driving power is required, and that, if necessary, thecarriage can be halted by hand. The cover is kept taut while beingrolled up, and it is also kept under tension while being pulled out andin intermediate positions by frictional forces. Here tautening can alsobe obtained by using braking elements that are direction-dependent andact on the drum and the transport mechanism.

According to one embodiment, two free-running couplings are connected toa common drive pulling element. Preferably, the coupling housings serveas the direction-changing wheels for the pulling element, which can bein the form of a belt, chain, or similar.

In another embodiment, the transport motor, constructed as a gear motor,is placed inside the drum, and the motor housing is rigidly connected tothe drum, while its drive shaft is coupled with a part of the frame ofthe transport mechanism in a manner enabling transmitting a torque. Thedrum is coupled to each of the front wheels of the transport mechanismby a freerunning coupling. Here, the drum can form the only connectingelement between the two lateral transport mechanisms. The transportmotor is entirely enclosed in the drum, and is not seen from theoutside. Since the motor housing is rigidly connected to the drum, thelatter can serve as the cable drum for the energysupplying cable. Thecable needs no control wires since the control is carried out from afixed location. Here, furthermore, no current path goes through arotating contact, as is required for a separate cable drum. The numberof separate parts is thus greatly reduced, correspondingly lowering thecost of the covering installation and the weight of the carriage.Therefore, very low drive power is required. Generally, a motor designedfor automobile window wipers will suffice.

Preferably, the support of the drive shaft on the frame of the transportmechanism is constructed as a brake in the manner of a slip clutch.Thus, when hitting a stop, the shaft, which is normally held, can turnwithout causing mechanical damage. Hence, automaticallyoperating limitstops are not absolutely essential. Preferably, the front wheel, too, issupported on the frame of the transport mechanism by a brake operatingat least during the roll-up procedure.

The front wheel, if possible, should have a greater outer diameter thanthe drum with rolled-up cover. An elastic substance should be providedfor the equalization of the differences in speed between front wheel anddrum. This insures that the carriage, in the pullingout procedure, isalways driven at a speed that is slightly higher than the unrollingspeed of the cover. Thus, the latter is also pulled taut during thisprocedure without addtional effort, keeping the carriage alwayscorrectly oriented laterally.

A slip clutch can serve as a means of equalization connected in tandemwith the free-running coupling between front wheel and drum. At the sametime, it is even simpler to form that equalizing element from a tire ofsoft, elastic, deformable material such as rubber, placed at thecircumference of the front wheel. Here, just as with the slip clutch,there is the possibility that the tire, on reaching the limits of itsholding forces on the surface, slips a little, thereby reducing thetension. With sufficient thickness of the tire, however, such slippingdoes not take place, since the equalizing deformation is limited to theportions of the circumference operative at the moment. During unrolling,always new sections of the circumference are deformed and then released.This is particularly pronounced when the tire has evenly distributed,radially protruding extrusions such as teeth or transverse ribs that arenot supported in the circumferential direction against each other.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a sectional view through arectangular swimming pool with a covering installation according to thepresent invention;

FIG. 2 is a plan view of the swimming pool with the coveringinstallation of FIG. 1;

FIG. 3 is a partial sectional view taken along line III- III In FIG. 1,through a drum end with transport mechanism;

FIG. 4 is a plan veiw of a drum end of an altered covering installationwith a conical cable drum part;

FIG. 5 is an embodiment according to FIG. 4; with a flat cable band;

FIG. 6 is a plan view of a transport mechanism with a caterpillar-likedrive belt;

FIG. 7 is a bottom view of the caterpillar arrangement of FIG. 6; and

FIG.- 8 is a side view of another embodiment of a cover carriage,according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawing and inparticular to FIGS. 1 and 2, a rectangular-shaped swimming pool hasfrontal walls 1, 2 and side wall 3, 4. A cover 30 is secured to asubstantially horizontal plane surface 5 by means of bolts 32 or thelike through its end 31, in the region of the frontal wall 1. Thesupporting surface 5 surrounds the swimming pool. The other end of thecover 30 is wound on a cylindrical drum 27 which connects two transportmechanisms 43, 44 to a common transport wagon 45. Each of the twotransport mechanisms has a transport frame 46, a front wheel 47, and tworear wheels 48.

In accordance with FIG. 3 at least one end of the drum is linked to adriving motor which serves as a transport motor 49. This motor ispreferably in the form of a conventional disc-wiping type of DC motorwhich may be operated from a 12 volt voltage supply. A bearing member 52is arranged on the driving shaft 51 of the transport motor, which islocated centrally with respect to the drum axis 50. The bearing member52 carries a first braked disc 53 which contacts the transport mechanismframe 46, through a second braked disc 54. A threaded portion 56 of thebearing member is passed through a bore of the frame 55, and issurrounded by a helical spring 57 which is positioned between the frameportion 55 and two nuts 58. The spring, the two nuts and the two wheels48 are covered from the exterior by a hood 59, which is placed over theframe portion 55.

The drum 27 has an end cap 60 which is fixed to a ball bearing 61, sothat the drum is held on the bearing member 52, through the ball bearing61. The end cap 60 is in a torque transmitting manner connected with thefirst coupling disc 62 which forms a free-running coupling with afurther coupling disc 63. The two coupling discs have elasticallybendable projections on their frontal surfaces. These projections are inthe form of short fiber portions which are inclined with respect to theplane of the disc in the circumferential direction, so that they reachinto each other in a first direction of rotation whereby they transmit atorque. In the opposite direction of rotation, howwever, theseprojections lie against their discs and thereby provide a freerunningeffect. The drum '27 is held on the bearing member 52 by way of theaforementioned ball bearing 61 and the hub of the wheel 64.

The second coupling disc 63 is in a torque transmitting manner connectedwith the wheel plate member 64 of the front wheel 47. A front drivingrim 65 is drawn onto this wheel plate 64. The circumferential portion ofthe rim 65 is subdivided through transverse notches into transverse ribs66 which project freely towards the exterior. The exterior diameter ofthe front wheel 47 is substantially larger than the diamter of the drum27 when the cover is fully wound onto the drum.

The wheel plate 64 has a hub portion 67 bent upwards, as shown in FIG.3, which lies between the bearing member 52 and the ball bearing 61. Inan alternate embodiment, this bearing arrangement can, for example, bein the form of a ball or roller bearing also on the bearing member 52,or outside of the ball bearing 61 on the end cap 60.

Two further coupling discs 68, 69 are arranged between the wheel plate64 and the brake disc 53. These further coupling discs 68, 69 areassociated with a second free-running coupling which is engaged in theopposite rotational driection corresponding to the engagement of thecoupling disc 62, 63, when the cover is wound on. The coefficient offriction between the coupling disc 69 and the brake disc 53, isessentially smaller than that prevailing between the brake discs 53, 54.A substantially smaller brake torque is thereby obtained on the frontwheel 47 than on the motor drive shaft 51. This smaller braking torqueoccurs only when winding up the cover, so that the transport mechanismsbecome braked only thereby and maintain the cover in stretchedcondition.

The free-running coupling 62, 63 can also be located between the'drum 27and the front wheel 47, with one or two discs forming, for example, aslip clutch. The entire combination of brake and coupling discs are, inall cases, only of substantially small thickness.

This thickness of this combination or package of brake and couplingdiscs are harmonized to the length of the bearing member 52, so that theshoulder surface 70 from which the threaded portion 56 extends, nevercomes into contact with the frame portion 55. Since the bearing member52 abuts against the frame portion 55 axially through the motor 49 onthe drum and through the nuts 58 and spring 57, the tension of thespring 57 between the frame portion and the end cap 60 is transmittedentirely onto the disc package therebetween.

The entire transport mechanism can be also removed from the drum withthe coupling and braking means, after removal of the hood 59 andloosening the nuts 58.

The bearing member 52 can be connected in axial direction with thedriving shaft 51, as might be assumed from above. This can be achievedthrough a threaded rod or similar means, which is drawn through anopening in the durm and in certain cases, through the end cap 60. It is,however, preferable to carry out this connection with the drive shaft bya mounted coupling which is insensitive to the direction of axle motion.This coupling then permits only small or no forcable torques to betransmitted to the shaft' The bearing member can then abut against theinner ring 71 of the ball bearing 61, through a shoulder surface. Theend cap 60 then forms a closed assembly with the transmit mechanism, andthis assembly can be mounted by itself onto the cylindrical end of thedrum, whereby the bearing member comes into contact with the drivingshaft 51. At the same time the end cap becomes coupled to the drumthrough, for example, two bolts.

Since here the axial supporting force is not transmitted through thetransport motor, the unit is able to function, due to the drivingprocedurre, when there is no transport motor at the particular drum end.Thus, it is possible to insert a transport motor at both ends or only atone, as required. Should the transport resistances prove too great for atransport motor, for example because of a change in span or in thetransport speed, it is only necessary to install a second transportmotor at the other drum end. However, the torque from one or two motorscan be taken off in an evenly distributed manner at both ends of thedrum 27, due to the great torsional stiffness of the drum Both transportmotors can also be connected in parallel and to common, permanentlyattached current connectors in the drum. It is also possible, in amanner to be explained below to attach the end of a currentcarryingcable to the drum, and to connect it directly to the motor connections.The cable also needs to concontrol device, to which, again, the cablescan be connected without rotary contacts.

When the carriage is to be transported from its position in FIGS. 1 and2 to the right, rolled-up, end position, then the transport motor 49 isconnected for a first direction of rotation, in which the motor housingwith the drum 27 rotates clockwise around driving shaft 51. The drivingshaft 51 is held to part 55 of the frame by the bearing member and brake53, 54 in a manner enabling torque transmission. Here, the freerunningcoupling 62, 63 is opened, i.e., the front wheel 47 is not driven butrolls off freely, while the freerunning brake 68, 69 transmits a smallbraking torque through brake 53, 54. Thus, the carriage 45 is pulled tothe right in FIGS. 1 and 2 only by the tension applied to cover 30.Since this tension is applied to the entire width of the cover, and thecarriage is slightly braked, an exact lateral orientation results,becoming more exact as the carriage approaches the cover end 31 attachedto the end of the basin. Additional centering devices are thus notrequired.

If the carriage 45 is now to be transported into the I coveringposition, i.e., to the left in F165. 1 and 2, then there is a torqueapplied at first counterclockwise to drum 27. But thefree-runningcoupling 62, 63, now closed, transmits the torque also to front wheel47. This wheel, indpendently of the instantaneous roll diameter, alwayshas a greater outer diameter than the drum with the cover, and rolls offdirectly onto the supporting area 5. Hence the wheel 47 attempts to movethe carriage 45 with a greater speed than that corresponding to theinstantaneous roll-off speed of the cover. This can be equalized aspreviously mentioned, by a slip clutch inserted between end cap and theclutch disc 62, or by sometimes letting the front wheel slide slightlypast supporting area 5. However, a practically complete equalization orcompensation is already obtained because the individual parts of thecircumference of tire are deformed in the direction of thecircumference, largely independently of each other, and then released.Thus, each transverse rib 66 arrives in a relaxed condition at thesupporting area 5 and is deformed until released, without influencingthe neighboring transverse ribs, by the difference between the drivedistances of the wheel circumferences and the cover. If actually thedifference between the distances is slightly larger than thedeformation, then, in each case, one of the ribs slides slightly,without deteriorating the even rolling procedure. In this direction ofrotation, too, the brake 53, 54 is activated when the cover is fullypulled out, or the transport movement is blocked by an obstruction.

As shown in FIG. 4, one end of drum 27 is formed into a conical surface74, bordered by two discs 73. A cylindrical cable containing only twoconductors 76, is wound onto the surface 74 in the manner of a spiral.The concial angle of the conical surface is so dimensioned that thewinding diameter increases for each rotation by approximately thesame,amount as the increase obtained in rolling up the cover, so thatthe cable is always under the same tension as the cover.

Another possibility is shown in FIG. 5. Here a flat cable ribbon 77 isprovided that is either permanently fixed to the edge of cover 30, or isrun through a tube 78 attached to the edge of the cover. The cableribbon has approximately the same thickness as the cover, and is rolledup just as the latter, without any significant resulting change indiameter.

In FIGS. 6 and 7, an endless caterpillar band 79,-

made of rubber or other appropriate material, has at least one outer,sub-divided gripping surface 80. This band is looped in circumferentialgrooves around front wheel 47 and two direction-changing wheels 48' insuch a way that it rests throughout the distance between the two wheels48' on supporting area 5. Here, too, a deformable tire can be providedaround the circumference of front wheel 47,'if there is no slip clutchincluded. But the loss here is small if some slip is allowed, as iscommon in belt drives. A further advantage of the caterpillar embodimentis the improvement in the directional stability of the transport drive.

1. A covering arrangement for open areas comprising, in combination,flexible cover means; winding drum means attached to one end of saidflexible cover means, said flexible cover means being windable on saiddrum means; reversible motor means linked to said drum means forunwinding said cover means from said drum means in one direction of saidmotor means, siad cover means being wound onto said drum means in thereverse direction of said motor means; wagon means for carrying saiddrum means and transporting said drum means; drive means on each side ofsaid drum means; and coupling means connected between said motor means,drum means and drive means so that said motor means is connected to saiddrive means when said motor means rotates in said one direction, saidmotor means being connected through said coupling to said drum meanswhen said motor means rotates in said reverse direction.
 2. Thearrangement as defined in claim 1 including directional dependentholding means on said drum means.
 3. The arrangement as defined in claim1 wherein said coupling means comprises two free-running couplings; andendless drive means connected to said free-running couplings; andhousing means for said coupling means and having disc means for drivingsaid couplings.
 4. The arrangement as defined in claim 1 wherein saidmotor means is within said drum means, the housing of said motor meansbeing fixedly connected to said drum means, the driving shaft of saidmotor means being supported on one of said drive means, said drive meanshaving wheel means, said drum means being connected to said wheel meansthrough said coupling means.
 5. The arrangement as defined in claim 4including slip clutch means on the frame of said drive means for brakingsaid driving shaft of said motor means.
 6. The arrangement as defined inclaim 4, including brake support means for said wheel means for brakingsaid wheel means at least during the winding of said cover means on saiddrum means.
 7. The arrangement as defined in claim 6, includingauxiliary wheel means supported on the edge of said open surface; andendless band drive means on the edge of said open surface and rollabletherefrom, said driving band means being slung on said wheel means andsaid auxiliary wheel means.
 8. the arrangement as defined in claim 4,wherein the outer diameter of said wheel means is substantially largerthan said drum means with said cover means wound on said drum means; andincluding compensating means for compensating for the difference of saiddiameters.
 9. The arrangement as defined in claim 8, including slipclutch means connected to said coupling means, said slip clutch meansand said coupling means being connected between said drum means and saidwheel means.
 10. The arrangement as defined in claim 8, wherein saidcompensating means comprises a rim of substantially soft elastic anddeformable material about the periphery of said wheel means.
 11. Thearrangment as defined in claim 10 wherein said rim has uniformlydistributed radial and outwardly directed projections.
 12. thearrangement as defined in claim 4, including brake means arrangedclosely to said coupling means; spring means for pressing said brakemeans and coupling means against each other, said wheel means beingcentrally located with respect to said drum means.
 13. The arrangementas defined in claim 12, wherein said brake means and said coupling meanshave disc-shaped elements, two disc-shaped elements of said couplingmeans having elastic projections directed against each other on theirperiphery.
 14. The arrangement as defined in claim 4, including powersupply cable means wound on said drum means, the variation in exteriordiameter from winding said cable means on said drum means correspondingsubstantially to the variation In exterior diameter due to winding ofsaid cover means on said drum means.
 15. The arrangement as defined inclaim 14, including a conically shaped winding surface on the side ofsaid drum means for winding on said conically shaped surface said cablemeans, said cable means being screw-shaped.
 16. The arrangement asdefined in claim 14, wherein said cable means comprises a substantiallythin band wound spirally on the side of said cover means.
 17. Thearrangement as defined in claim 4, including a bearing member for saiddrum means and connectable torque transmittingly with the driving shaftof said motor means as well as a portion of the frame of said drivemeans.
 18. The arrangement as defined in claim 4, including connectingmeans at each end of said drum means for selectively connecting to saidmotor means and said drive means.
 19. The arrangement as defined inclaim 1, including limit switch means for contactless control of saidmotor means, said motor means being a low voltage braking motor.
 20. Thearrangement as defined in claim 1, including energy storage means onsaid wagon means.
 21. The arrangement as defined in claim 20, includingenergy supply means connectable to said energy storage means in one endposition of said wagon means.